Heating, ventilation, and air conditioning (HVAC) systems can be used to regulate the temperature of a room or space. Existing HVAC systems use a discharge set point to control the speed of a compressor and the temperature difference between a space temperature and a space temperature set point (e.g. space temperature delta) to control the speed of a supply fan. As a result of the compressor being an important factor in controlling the capacity of a refrigeration system, existing systems put an emphasis on controlling the discharge air temperature over controlling the space temperature. The discharge air temperature can fluctuate over a much greater range than the space temperature delta, which may cause the speed of a compressor to be higher initially than what is needed to cool a space and can lead to higher energy consumption and reduced reliability. It is desirable to provide an HVAC system that improves the efficiency of regulating the temperature of a space.